1. Field of the Invention
The present invention relates generally to meter centers for electrical power distribution systems and, more particularly, to a meter center including a multiple meter socket assembly structured to provide a plurality of phase combinations among a plurality of meters. The invention also relates to multi-phase multiple meter socket assemblies for meter centers.
2. Background Information
Meter centers including a plurality of watt-hour meters are commonly used to measure electric power consumed by the various tenants of a multi-unit residential site (e.g., without limitation, an apartment building) or commercial site (e.g., without limitation, an office complex).
FIGS. 1 and 2 show a conventional meter center assembly 1, which generally consists of a cabinet 3 having an internal longitudinal wall 5 that divides the cabinet 3 into side-by-side meter and disconnect switch compartments 7, 9. A plurality of plug-in, socket type watt-hour meters 11 are mounted within the meter compartment 7, one meter 11 for each tenant circuit which is to be metered. Thus, in the example of FIG. 1, the meter center 1 accommodates four tenant circuits each served by its own meter 11. Each tenant circuit is also provided with a disconnect switch 13 such as, for example, a circuit breaker, which is mounted within the disconnect switch compartment 9.
Electric power is provided to the meter center 1 by feeder buses 17 which are electrically connected to the utility lines (not shown) that supply power. Specifically, as shown in FIG. 2, three phase buses 17A, 17B, 17C and a neutral bus 17N extend horizontally through the cabinet 3 for connection to the utility lines (not shown). A set of supply buses 27 extend vertically within the meter compartment 7 and electrically connect to the feeder buses. More specifically, the supply buses 27 generally comprise a pair of spaced apart bus bars 29R, 29L which are each electrically connected to one of the feeder buses 17A, 17B, 17C by one of the phase balancers 47A, 47B. For example, the left supply bus 29L in the example of FIG. 2 is electrically connected to the phase A feeder bus 17A by phase balancer 47A, and the right supply bus 29R is electrically connected to the phase B feeder bus 17B by phase balancer 47B. Phase balancer 47A generally consists of a cylindrical sleeve 49 and bolt 51. Phase balancer 47B generally consists of a Z-shaped member 53 and bolts 55. Thus, the entire meter center 1 is configured in the same manner, in this case phase AB, although it will be appreciated that it could also be entirely phased AC (for feeder buses 17A and 17C) or BC (for feeder buses 17B and 17C).
Accordingly, it will be appreciated that known conventional meter centers provide only one phase configuration within the entire cabinet. In other words, the entire cabinet must be phased AB, AC, or BC. Among other disadvantages, this makes phase balancing (i.e., distributing the electrical load) difficult where, for example, multiple meter centers are ganged together in order to individually meter power consumption by multiple different tenants in the same building or facility.
There is, therefore, room for improvement in meter centers and in multiple meter socket assemblies therefor.